摘要
针对惯性/天文组合导航中将天文传感器测量信息从天球坐标系到地球坐标系转换的问题,研究了其转换过程中涉及到的时间系统和坐标转换关系,前者包括世界时、地球时、太阳系质心力学时、原子时和协调世界时等时间概念,后者包括岁差、章动、视恒星时和极移等旋转变换。对坐标转换过程中小于0.1″的因素进行了忽略和近似简化,误差分析表明,除地球自转角的计算需要比较精确的UT1时间外,其他天文参数计算中的时间输入均可直接使用UTC时间代替。仿真结果显示,所提简化算法的转换精度达到了0.2″,满足角秒级的天文传感器测姿精度需求。
Aiming at converting the astronomical sensor measurement information from the Celestial coordinate system to the Earth coordinate system in inertial/celestial integrated navigation,the time system including UT,TT,TDB and the coordinate system conversion relationship which composed by precession,nutation,apparent sidereal time and polar motion involved in the conversion process are studied.In the process of coordinate conversion,items less than 0.1"are ignored and approximately simplified.The error analysis results show that except for the calculation of the rotation angle of the Earth,which requires a more accurate UT1 time,the time input in the calculation of other astronomical parameters can be replaced by UTC time.The simulation results show that the conversion accuracy of the proposed simplified algorithm can reach about 0.2"accuracy,which meets the arc-second-level astronomical sensor attitude accuracy requirements.
作者
严恭敏
戴晨杰
陈若彤
YAN Gongmin;DAI Chenjie;CHEN Ruotong(School of Automation,Northwestern Polytechnical University,Xi’an 710072,China)
出处
《中国惯性技术学报》
EI
CSCD
北大核心
2022年第1期89-95,103,共8页
Journal of Chinese Inertial Technology
基金
国家自然科学基金(51879219)。
